Like other hypsilophodonts it had a tail stiffened by bony tendons. Held straight behind it, it's tail helped Parksosaurus keep it's balance. It was a smallish dinosaur - roughly around 2-4 meters long. It didn't have any particular anatomical features and was a distant relative of the bigger hadrosaurs, such as Edmontosaurus.
Parksosaurus lived during the Late Cretaceous period from 72-65 million years ago, living up until the extinction of the dinosaurs.
Parksosaurus was a smallish but relatively large dinosaur for its size, roughly around 2-4 meters long and weighed at 45 kilograms.